Can the exotic pathogen Nosema ceranae affect the amount of Cucurbita maxima pollen grains transported by the native bee Eucera fervens?

GREGORIO FERNANDEZ DE LANDA; FACUNDO RENÉ MEROI ARCERITO; CAMILA CORTI; PABLO DAMIÁN REVAINERA; ANABELLA RITA NICOLLI; FRANCISCO ZUMPANO; CONSTANZA BRASESCO; SILVINA QUINTANA; MATEO FERNANDEZ DE LANDA; FACUNDO RAMOS; ROMINA PETRIGH; MARTIN JAVIER EGUARAS; LEONARDO GALETTO; MATÍAS MAGGI

Arthropod-Plant Interactions

Springer Science and Business Media B.V.

Año: 2022 vol. 16 p. 607 - 615

Eucera and Xenoglosa are the two most frequent squash pollinators, and they both rely solely upon plants of the genus Cucurbita for pollen intake to feed their ofspring. The present study reports the frst case of Eucera fervens individuals infectedwith Nosema ceranae spores and assesses the possible impact of this microsporidian on the squash pollen transportationcarried by this South American native bee. From the total 963 bees visiting pumpkin fowers, the most frequent bee specieswas E. fervens (89.8%). A total of 90 bees were sampled for pollen count and Nosema detection. Bees were carrying anaverage of 62 pollen grains (7–426) and an average of 19 Cucurbita pollen grains (1–93). Nosema was present in 98% ofthe samples (71/72), while its mean intensity was 1.65× 106 spores (1.5× 105–6.78× 106). A positive correlation betweenthe total pollen grains and the number of pumpkin pollen grains transported by E. fervens was observed. The Cucurbitamaxima pollen transported by E. fervens was not explained by N. ceranae spores loads. Nevertheless, a positive correlationbetween the total pollen grains transported by E. fervens and the N. ceranae intensity was observed suggesting and efect ofthe microsporidian on bee behavior.